Protective Helmet

ABSTRACT

A protective helmet with a helmet shell ( 3 ) which, when it is in use, at least partly encloses the user&#39;s head with the exception of the face area, a chin guard ( 1 ) which, when it is in use, encloses the lower parts of the user&#39;s face area, as well as a visor ( 4 ) preferably arranged in a pivoting manner on the helmet shell ( 3 ) for covering the visual field opening between helmet shell ( 3 ) and chin guard ( 1 ), with the chin guard ( 1 ) comprising two sections ( 1   a   , 1   b ) which are movable relative to each other. It is provided in accordance with the invention that each of the two chin guard sections ( 1   a   , 1   b ) is pivotally arranged on the helmet shell ( 3 ), and said pivoting arrangement of the chin guard sections ( 1   a   , 1   b ) on the helmet shell ( 3 ) takes place every time by means of a flexible plate element ( 2 ) which connects the helmet shell ( 3 ) to the corresponding chin guard section ( 1   a   , 1   b ).

The invention relates to a protective helmet with a helmet shell which when used at least partly encloses the head of the wearer with the exception of the face area, a chin guard which when used encloses the lower parts of the face area of the wearer, as well as a visor preferably arranged in a pivoting manner on the helmet shell for covering the visual field opening between helmet shell and chin guard, with the chin guard comprising two sections which are movable relative to each other, in accordance with the preamble of claim 1.

Such protective helmets ameliorate or prevent injuries in the cranial region of the wearer of the helmet, especially in the case of motorcycle accidents. One can distinguish between several variants.

In EP 0 433 182 for example, a helmet is described with two chin guard sections which are movable relative to each other and which are held in a displaceable manner on the helmet shell. The opening of the helmet cannot be extended downwardly very much in this helmet when merely displacing the chin guard sections in the direction towards the interior of the helmet. Moreover, no pretension can be realized, neither in the opened position nor in the closed position of the chin guard sections. Such a helmet is also difficult to produce from a technical standpoint and does not allow any link joints between the two chin guard sections. As a result, there cannot be any synchronization of the chin guard sections in their respective path of movement.

Helmets are further known in which the face area is open (so-called “jet helmets”). Although such helmets offer the benefit of fresh air, it is disadvantageous in rain and cold weather. Moreover, the face and chin areas are protected only insufficiently in the case of an accident.

Cross helmets are especially used in the field of sports with single-track vehicles and also have a relatively large visor opening in order to ensure important supply of air in the case of bodily exertion. In contrast to jet helmets, these helmets have a stable chin guard in order to offer sufficient protection in the case of often frequent falls.

So-called flip-up or system helmets have an integral massive chin guard to which the visor is also mostly attached. The chin guard can flipped upwardly via a substantially horizontal pivoting axis, so that putting on and removing the helmet is facilitated. Although these types of helmets facilitate putting on the helmet since the helmet is put on when the chin guard is flipped upwardly, they do not offer any additional form fit in the chin area because the chin guard only pivots horizontally downwardly. Helmets of this kind can also not be put on or removed with spectacles.

According to a further embodiment a helmet shell is provided which, when it is used, nearly completely encloses the head of the wearer with the exception of the face area, a chin guard which, when it is used, completely encloses the lower portions of the face area of the wearer, and a visor preferably arranged in a pivotable manner on the helmet shell for covering the visual field opening between helmet shell and chin guard. The fastening to the head of the wearer occurs via a chin strap which is tensioned in the chin area of the wearer after putting on the helmet. Helmets of this kind (so-called “integral helmets”) are widely used, but come with the disadvantage that putting them on and taking them off is impractical. Especially in the case of accidents, the difficulty in removing the helmet may lead to dangerous situations, especially in the case of throat injuries.

All helmet types also have the disadvantage that different helmet sizes are offered in order to choose the model with the best fit for the different head sizes. It has been seen in practice however that in this way it is possible to achieve the best possible fit of the helmet only within limits. In practice, the consumer therefore often has the choice between a helmet which offers a good fit but is difficult to put on and take off, or a helmet that is easy to put on and take off but offers only an adverse fit. Moreover, the chin strap which is necessary in helmets of this kind for fixing the helmet to the head of the wearer offers an inadequate hold especially in the chin and neck region, which has an even stronger effect in an adverse fit of the helmet. This disadvantage will be especially noticeable at higher speeds where additional wind pressure forces will act and might push up the helmet. Moreover, air flows entering the helmet from below as a result of the lack of fit between helmet and the front throat region may impair riding comfort because they cause unpleasant wind noise and coldness.

Chin straps also have the disadvantage that they might be difficult to handle, especially when wearing gloves. They can also only be operated with difficulty with one hand. Moreover, numerous locking systems for the chin strap are offered whose operation may pose difficulties when confronted with an unknown system. It has actually been noticed in practice that in accident situations the paramedics often have difficulties in opening the locking system of the chin straps and lose valuable time.

It is therefore the goal of the invention to realize a protective helmet which can be put on and taken off easily and offers better hold, especially in the chin and neck region. This helps to ensure that the sliding of the helmet over the back of the head is prevented, especially in the course of accident situations. The term used in this field of the invention is designated as “strip-off behavior” which is to be improved in the protective helmet in accordance with the invention. The invention shall further ensure the realization of better aerodynamic and aeroacoustic properties and better protection against wind, dirt and coldness.

These objects are achieved by the features of claim 1 or 2. Claim 1 and 2 each relate to a protective helmet with a helmet shell which, when it is in use, surrounds at least partially a user's head except the face area, a chin guard which, during the helmet use, surrounds the lower parts of the face area of the helmet user and a visor preferably pivotally positioned on the helmet shell for forming an opening for the face between the helmet shell and the chin guard, with said chin guard being provided with two sections which are movably mounted on the helmet shell. It is provided in accordance with claim 1 that each of the two chin guard sections is pivotally arranged on the helmet shell and said pivotable arrangement of the chin guard sections on the helmet shell takes place every time by means of a flexible plate element which connects the helmet shell to the corresponding chin guard section. It is provided in accordance with claim 2 that the two chin guard sections are connected with each other via a link joint in their respective upper sections. As a result, there is always a synchronous closing of the two chin guard sections, even when different closing pressure is exerted by the hands on the two chin guard sections. The closing of the chin guard sections can also be made with one hand by this measure in particular.

As a result of the pivotable arrangement of the chin guard sections it is possible at first to extend the helmet opening prior to putting on or taking off the helmet, thus facilitating putting on and taking off the helmet. Both chin guard sections will usually be pivotably arranged in a manner, so that each of the two chin guard sections will pivot downwardly and to the outside about different axes each during the opening, so that the two chin guard sections move away from each other during the opening. During the closing of the chin guard sections, they move towards each other again, thus reducing the helmet opening.

It is also possible as a result of the measures in accordance with the invention to arrange the chin guard sections in such a way from a constructional viewpoint that after putting on the helmet the helmet opening is reduced even further, thus considerably further improving hold especially in the chin area because a sufficiently large helmet opening for putting on and taking off the helmet is ensured through the pivoting capability of the chin guard sections. It can be provided according to claim 3 for example that the two chin guard sections each have a chin protection surface in their lower section which protrudes laterally in the direction towards the interior of the helmet. The opening of the helmet is additionally reduced during the closing of the chin guard sections, thus not only improving hold but also enabling improved aerodynamic and aeroacoustic properties of the helmet as well as improved protection against wind, dirt and coldness, as will be explained below in closer detail.

An especially advantageous embodiment for the chin guard sections is proposed in claim 4. Claim 4 provides that the chin guard sections each comprise a fastening area at their end facing the helmet shell and a closing area with a closing surface at their end averted from the helmet shell, with the two closing surfaces being spaced from one another in an opening position of the two chin guard sections and rest against each other in a closing position which can be reached by pivoting the two chin guard sections.

The feature of claim 5 is advantageous in that a closing mechanism is arranged in the area of the closing surfaces which spatially fixes the two chin guard sections in their closing position on each other. The closing mechanism can be arranged in the area of the closing surfaces approximately on the surfaces which are oriented downwardly and can be arranged as a clasp for example.

Claim 6 provides that one of the closing surfaces comprises a groove and the other closing surface comprises a spring associated with the groove, with groove and spring engaging into each other in the closing position. As a result, shearing forces of the two chin guard sections can be absorbed better in the case of an impact and the load on the link joint and the closing mechanism can be reduced. The proper functioning of the closing mechanism in the case of an accident and the loads on the chin guard sections caused thereby can thus be ensured.

When the two chin guard sections are pretensioned in their opening position according to claim 7, the two chin guard sections automatically swivel to the opening position after the opening of the closing mechanism for example. When a flexible plate element is provided, the pretension can be achieved in such a way that the plate element is in its tension-free position in the opening position, whereas it is placed under tension in the course of the closing movement.

It is provided according to claim 8 that the fastening area of the two chin guard sections each terminates with a lateral surface facing the helmet shell, which lateral surface rests on one support surface of the helmet shell in the closing position of the chin guard section and is spaced from the support surface in the opening position of the chin guard sections. By supporting the chin guard sections on the helmet shell in the closing position, better protection is ensured in the case of forces which act from below on the chin guard sections. When it is provided especially in accordance with claim 9 that the lateral surface of the fastening area of the chin guard sections and the support surface of the helmet shell are each arranged in a stepped manner, with the stepped sections engaging into each other in the closing position of the chin guard sections, it is possible to better absorb shearing forces between the chin guard section and the helmet shell.

According to claim 10, the chin guard surface is provided with a removable padding on the side facing the interior of the helmet. The removability ensures that padding with different thicknesses can be used, so that the helmet can be adjusted better to different head sizes. Furthermore, the removable padding can also be cleaned more easily.

Claim 11 provides that the lateral surface of the fastening area converges along its longitudinal extension via a terminating surface in an obtuse manner into the chin guard surface and the terminating surface rests on a holding shoulder of the helmet shell in the closing position of the chin guard sections. Forces which act frontally on the chin guard sections are thus absorbed better by the helmet.

When the two chin guard sections are further overlapped by the visor in their closing position in accordance with claim 12 or rest on the bottom edge of the visor, the chin guard sections can be opened or closed independent from the visor.

The invention is now explained in closer detail by reference to the enclosed drawings, wherein:

FIG. 1 shows a perspective side view of an embodiment of a protective helmet in accordance with the invention in the closed position of the chin guard sections;

FIG. 2 shows a perspective side view of the embodiment of FIG. 1 in an open position of the chin guard sections;

FIG. 3 shows a perspective front view of a protective helmet in accordance with the invention in the embodiment of FIG. 1 in the closed position of the chin guard sections;

FIG. 4 shows a perspective front view of a protective helmet in accordance with the invention in the embodiment of FIG. 1 in the opened position of the chin guard sections;

FIG. 5 shows a sectional view of the representation according to FIG. 4, in which the chin guard sections are in the opened position;

FIG. 6 shows a sectional view of the representation according to FIG. 3, in which the chin guard sections are in the closed position;

FIG. 7 shows a perspective view of an embodiment of the helmet shell of a protective helmet in accordance with the invention;

FIG. 8 shows a perspective view of an embodiment of the chin guard sections of a protective helmet in accordance with the invention for their closed position, and

FIG. 9 shows a detailed view of a perspective view of the embodiment of FIG. 1 of a protective helmet as seen from below.

Reference is made at first to FIG. 1 which shows a perspective side view of an embodiment of a protective helmet in accordance with the invention, comprising a helmet shell 3 and chin guard sections 1 a, 1 b (only chin guard section 1 a is visible in FIG. 1), with the latter being in their closed position. According to the illustrated embodiment, the chin guard sections 1 a, 1 b are each fastened to the helmet shell 3 via a flexible plate element 2. The plate element 2 is made of a durably flexible, fracture-proof and tear-proof material such as POM (polyoxymethylene/polyacetal) or PC, and is fastened to the outer surface of the helmet shell 3 by a glued, riveted or clasped connection. FIG. 1 shows a fastening by means of riveted connections 5 for example. The plate elements 2 can preferably also be sunk into the helmet shell 3 in the interests of improved aerodynamics, thus leading to a smooth surface. A visor 4 is preferably also arranged in a pivoting manner on the helmet shell 3. A padding 12 is usually also provided in the interior of the helmet shell 3.

The plate elements 2 are wound off over the helmet shell 3 and the respective chin guard sections 1 a, 1 b in such a way that only parallel tension lines parallel to the pivot axis are obtained during pivoting movements of the chin guard sections 1 a, 1 b. Deformations of the plate elements 2 are thus avoided which are not used for guiding the chin guard sections 1 a, 1 b. Material stresses of the plate elements 2 are thus reduced.

Moreover, the fastening elements 5 between the plate elements 2 and the helmet shell 3 as well as chin guard sections 1 a, 1 b are less stressed. Preferably, the two chin guard sections 1 a, 1 b are pretensioned in their opening position. Such a pretension can be achieved in such a way that the plate element 2 is in its tension-free position when situated in the opening position, whereas it is subjected to tension in the course of the closing movement. Other embodiments of a pivoting arrangement of the chin guard sections 1 a, 1 b on the helmet shell 3 are possible insofar as they ensure a pivoting capability of the chin guard sections 1 a, 1 b for enlarging the helmet opening in the course of the transition from the closing position to the opening position and guarantee secure fastening of the chin guard sections 1 a, 1 b on the helmet shell 3.

Both chin guard sections 1 a, 1 b will usually be arranged in a pivoting manner in such a way that each of the two chin guard sections 1 a, 1 b will pivot downwardly and outwardly by different axes each, so that the centers of gravity of the two chin guard sections 1 a, 1 b will move away from each other during the opening. During the closing of the chin guard sections 1 a, 1 b they will move towards one another, thus reducing the helmet opening. The pivoting axis defined by the helmet shell 3, the chin guard sections 1 a, 1 b and the plate elements

is thus oriented in an oblique way each. With respect to FIG. 1 it extends approximately from the bottom left to the top right.

FIG. 2 shows a perspective side view of the embodiment of FIG. 1 in an opened position of the chin guard sections 1 a, 1 b. As was already mentioned, it is possible as a result of the measures in accordance with the invention to provide the chin guard sections 1 a, 1 b with such a construction that after putting on the helmet the helmet opening is reduced even further, which thus considerably improves the seat of the helmet especially in the chin region because a sufficiently large helmet opening for putting on and taking off the helmet is ensured through the pivoting capability of the chin guard sections. FIG. 2 shows for example that the two chin guard sections 1 a, 1 b each comprise in their lower region a chin guard surface 6 protruding laterally in the direction of the interior of the helmet. The opening of the helmet is thus additionally reduced in this way during the closing of the chin guard sections 1 a, 1 b because the chin guard surfaces 6 move towards one another and finally rest flush against one another in the closing position of the chin guard sections 1 a, 1 b. This not only improves the seat of the helmet but also provides better aerodynamic and aeroacoustic properties of the helmet as well as improved protection against wind, dirt and coldness.

The chin guard sections 1 a, 1 b are subdivided in the following into a fastening area 7 which is located at the end facing the helmet shell 3 and a closing area 13 which is located at the end averted from the helmet shell 3. The closing area 13 comprises a closing surface 8 each, with the two closing surfaces 8 being spaced apart from one another in an opening position of the two chin guard sections 1 a, 1 b and rest against each other in a closing position which can be achieved by pivoting the two chin guard sections 1 a, 1 b. The closing surface 8 can also be provided with a rubber surface seal (not shown in FIGS. 1 to 9) for protection against the penetration of wind and wetness.

The two chin guard sections 1 a, 1 b are mutually connected to each other in their upper sections of the closing areas 13 via a link joint. As a result, there is always a synchronous closing of the two chin guard sections 1 a, 1 b, even when a different closing pressure is exerted with the hands on the two chin guard sections 1 a, 1 b. As already mentioned, the closing of the chin guard sections 1 a, 1 b can also occur by means of one hand as a result of this measure because a movement of the first chin guard section 1 a for example is transmitted to the second chin guard section 1 b by the link joint 10. A closing mechanism 11, 14 can also be arranged in the area of the closing surfaces 8, which closing mechanism fixes the two chin guard sections 1 a, 1 b spatially in their closed position against one another. FIG. 2 shows a possible embodiment of such a closing mechanism 11, 14 with the help of a lever 14 which cooperates with a pin 11. Lifting the lever 14 releases the pin 11 and the two chin guard sections 1 a, 1 b pivot into their opening position as a result of the pretension of the plate element 2. Such a lever 14 can also be operated with one hand, which is especially advantageous and which should also be taken into account when choosing the closing mechanism 11, 14.

The link joint 10 should therefore be arranged in the respective upper sections of the closing areas 13 because preferably each of the two chin guard sections 1 a, 1 b should pivot downwardly and to the outside during the opening, so that the two chin guard sections 1 a, 1 b move away from each other during the opening.

FIG. 2 further shows that one of the two closing surfaces 8 comprises a groove 9 and the other closing surface 8 comprises a spring 15 associated with the groove 9 (see FIG. 4 for example), with groove 9 and spring 15 engaging into each other in the closing position. As a result, the shearing forces of the two chin guard sections 1 a, 1 b can be better absorbed in case of impact and the load of the link joint 10 and the closing mechanism 11, 14 can be reduced. The proper functioning of the closing mechanism 11, 14 in the case of an accident and the thus caused stresses on the chin guard sections 1 a, 1 b can thus also be ensured.

FIG. 3 shows a perspective front view of a protective helmet in accordance with the invention in the embodiment of FIG. 1 in the closed position of the chin guard sections 1 a, 1 b. Air slits 23 can be seen in the front sections of the chin guard sections 1 a, 1 b which ensure sufficient ventilation of the interior of the helmet and prevent misting of the visor 4. FIG. 4 shows a perspective front view of a protective helmet in accordance with the invention in the embodiment of FIG. 1 in an opened position of the chin guard sections 1 a, 1 b, with spring 15 being shown which cooperates with groove 9 (see FIG. 2).

FIGS. 5 and 6 each show a sectional view of the illustration according to FIG. 4, with the chin guard sections 1 a, 1 b being located in the opened position in FIG. 5 and in the closed position in FIG. 6. FIGS. 5 and 6 also show the inner lining of helmet shell 3. Helmet shell 3 itself represents the outermost protective shell and distributes the forces on impact. For producing the helmet shell 3 it is recommended to use duroplastic materials, glass fiber materials embedded in plastic (GRP), or thermoplastic materials such as polycarbonate (PC), polyamide (PA) or acrylonitrile butadiene styrene (ABS). The padding 12 can be composed of a protective padding 12 a which absorbs the energy released during an impact in the interior of the helmet and consists of polystyrene and of a comfort padding 12 b which fixes the helmet to the user's head in a fixed and comfortable way and is made of foamed material for example. The chin guard sections 1 a, 1 b and their chin guard surfaces 6 are also provided on the surfaces facing the interior of the helmet with a protective padding 12 a and a comfortable padding 12 b. It is advantageous when in the opened position of the chin guard sections 1 a, 1 b their padding 12 continues the padding 12 of the helmet shell 3 without any interruption in order to facilitate putting on and taking off the helmet (see FIG. 5). In the closed position of the chin guard sections 1 a, 1 b the padding 12 of the chin guard sections 1 a, 1 b rests tightly under the user's ears, but offers enough free space for comfortable wearing and unrestricted hearing in the region of the ears themselves. Wearing spectacles is also possible in an easy and comfortable fashion (FIG. 6). The padding 12 of the chin guard sections 1 a, 1 b and their chin guard surfaces 6 are also preferably removable. As a result of the removability, different types of padding 12 with different thicknesses can be used, so that the helmet can be better adjusted to different head sizes.

The seat of the helmet is thus improved. Moreover, the removable padding 12 can also be cleaned more easily. Preferably, the helmet shell 3 also comprises neck protection with respective padding (not shown in FIGS. 1 to 9).

FIGS. 5 and 6 also show that the fastening area 7 of the two chin guard sections 1 a, 1 b each terminate in a side surface 16 facing the helmet shell 3, which side surface rests on a support surface 17 of the helmet shell 3 in the closing position of the chin guard sections 1 a, 1 b (FIG. 6), and is spaced from the support surface 17 in the opening position of the chin guard sections 1 a, 1 b (FIG. 5). As a result of the support of the chin guard sections 1 a, 1 b on the helmet shell 3 in the closing position, better protection is offered in case of forces acting from below on the chin guard sections 1 a, 1 b. In particular, the side surface 16 of the fastening area 7 of the chin guard sections 1 a, 1 b and the support surface 17 of the helmet shell 3 can each be provided with a stepped arrangement, so that a fold 21 is formed in the side surface 16 and a support nose 22 in support surface 17. In the closing position of the chin guard sections 1 a, 1 b, the stepped sections engage into each other, such that the support noses 22 come to lie in the fold 21 (FIG. 6). As a result, shearing forces between the chin guard sections 1 a, 1 b and the helmet shell 3 can thus be absorbed better (FIG. 6).

FIG. 7 shows a perspective view of an embodiment of the helmet shell 3 of a protective helmet in accordance with the invention, with the padding 12 having been omitted. The stepped arrangement of the support surface 17 by forming the support nose 22 can be seen in particular. In comparison with FIG. 8 which shows a perspective view of an embodiment of the chin guard sections 1 a, 1 b, it can be seen how the support nose 22 is adjusted to the fold 21 of the side surface 16, so that the support nose 22 is received by the fold 21 in the closed position of the chin guard sections 1 a, 1 b. In this position, the side surfaces 16 and the support surface 17 rest upon one another. FIG. 7 further shows that in the interest of improved aerodynamics the plate elements 2 can be sunk in a stepped area 18 of the helmet shell 3 and the chin guard sections 1 a, 1 b, thus leading to a smooth outside surface of the helmet shell 3.

FIG. 8 further shows that the side surfaces 16 of the fastening area 7 converges in an obtuse manner into the chin guard surface 6 along its longitudinal extension via a terminating surface 20. FIG. 7 shows again that the helmet shell 3 comprises a holding shoulder 19. The terminating surface 20 rests on the holding shoulder 19 of helmet shell 3 especially in the closed position of the chin guard sections 1 a, 1 b. Forces acting frontally on the chin guard sections 1 a, 1 b are thus better absorbed by the helmet. FIG. 8 further clearly shows how the chin guard sections 1 a, 1 b and their chin guard surfaces 6 are provided with a padding 12 on the surfaces facing the interior of the helmet. Padding 12 of the chin guard surfaces 6 can be provided with different thicknesses for adjustment to different head sizes and is preferably removable. Moreover, padding 12 will also usually be provided on the inner side surfaces of the chin guard sections 1 a, 1 b. They are not shown in FIG. 8 however.

FIG. 9 shows a detailed sectional view of a perspective view of the embodiment of FIG. 1 of a protective helmet in accordance with the invention as seen from below. It especially shows a possible embodiment of the closing surfaces 8 and the closing mechanism 11, 14. As was already mentioned, one of the closing surfaces 8 comprises a groove 9 and the other closing surface 8 a spring 15 associated with said groove 9 (also see FIGS. 2 and 4), with groove 9 and spring 15 engaging into each other in the closing position. The link joint 10 is further clearly shown. The closing mechanism 11, 14 consists in the shown embodiment of a lever 14 which cooperates with a pin 11. When lever 14 is lifted, pin 11 is released, and the two chin guard sections 1 a, 1 b pivot into their opening position as a result of the pretension of the plate element 2. Other embodiments of the closing mechanism 11, 14 are possible. In any case, they must be sturdy and easy to use.

A protective helmet is thus realized with the help of the invention which is easy to put on and take off and offers a better seat, especially in the jaw and neck region. The “strip-off behavior” is thus especially optimized. The helmet in accordance with the invention further has exceptional aerodynamic and aeroacoustic properties and offers improved protection against wind, dirt and coldness. According to first tests of the applicant, the helmet in accordance with the invention has proven to be the quietest full-visor helmet that is currently available. 

1. A protective helmet with a helmet shell (3) which, when it is in use, at least partly encloses the user's head with the exception of the face area, a chin guard (1) which, when it is in use, encloses the lower parts of the user's face area, as well as a visor (4) preferably arranged in a pivoting manner on the helmet shell (3) for covering the visual field opening between helmet shell (3) and chin guard (1), with the chin guard (1) comprising two sections (1 a, 1 b) which are movable relative to each other, characterized in that each of the two chin guard sections (1 a, 1 b) is pivotally arranged on the helmet shell (3), and said pivoting arrangement of the chin guard sections (1 a, 1 b) on the helmet shell (3) takes place by means of a flexible plate element (2) which connects the helmet shell (3) to the corresponding chin guard section (1 a, 1 b).
 2. A protective helmet with a helmet shell (3) which, when it is in use, at least partly encloses the user's head with the exception of the face area, a chin guard (1) which, when it is in use, encloses the lower parts of the user's face area, as well as a visor (4) preferably arranged in a pivoting manner on the helmet shell (3) for covering the visual field opening between helmet shell (3) and chin guard (1), with the chin guard (1) comprising two sections (1 a, 1 b) which are movable relative to each other, characterized in that each of the two chin guard sections (1 a, 1 b) is pivotally arranged on the helmet shell (3), and the two chin guard sections (1 a, 1 b) are connected with each other in their respective upper sections via a link joint (10).
 3. A protective helmet according to claim 1, wherein the two chin guard sections (1 a, 1 b) each have a chin protection surface (6) in their lower section which protrudes laterally in the direction towards the interior of the helmet.
 4. A protective helmet according to claim 1, wherein the chin guard sections (1 a, 1 b) each comprise a fastening area (7) at their end facing the helmet shell (3) and a closing area (13) with a closing surface (8) at their end averted from the helmet shell (3), with the two closing surfaces (8) being spaced from one another in an opening position of the two chin guard sections (1 a, 1 b) and rest against each other in a closing position which can be reached by pivoting the two chin guard sections (1 a, 1 b)
 5. A protective helmet according to claim 4, wherein a closing mechanism (11, 14) is arranged in the area of the closing surfaces (8) which spatially fixes the two chin guard sections (1 a, 1 b) against each other in their closing position.
 6. A protective helmet according to claim 4, wherein one of the closing surfaces (8) comprises a groove (9) and the other closing surface (8) comprises a spring (15) associated with the groove (9), with groove (9) and spring (15) engaging into each other in the closing position.
 7. A protective helmet according to claim 1, wherein the two chin guard sections (1 a, 1 b) are pretensioned in their opening position.
 8. A protective helmet according to claim 4, wherein the fastening area (7) of the two chin guard sections (1 a, 1 b) each terminates in a lateral surface (16) facing the helmet shell (3), which lateral surface rests on one support surface (17) of the helmet shell (3) in the closing position of the chin guard section (1 a, 1 b) and is spaced from the support surface (17) in the opening position of the chin guard sections (1 a, 1 b).
 9. A protective helmet according to claim 8, wherein the lateral surface (16) of the fastening area (7) of the chin guard sections (1 a, 1 b) and the support surface (17) of the helmet shell (3) are each arranged in a stepped manner, with the stepped sections engaging into each other in the closing position of the chin guard sections (1 a, 1 b).
 10. A protective helmet according to claim 3, wherein the chin guard surface (6) is provided with a removable padding (12) on the side facing the interior of the helmet.
 11. A protective helmet according to claim 4, wherein the lateral surface (16) of the fastening area (7) converges along its longitudinal extension via a terminating surface (20) in an obtuse manner into the chin guard surface (6), and the terminating surface (20) rests on a holding shoulder (19) of the helmet shell (3) in the closing position of the chin guard sections (1 a, 1 b)
 12. A protective helmet according to claim 1, wherein the two chin guard sections (1 a, 1 b) are overlapped by the visor (4) in their closing position or rest on the bottom edge of the visor (4). 